1 вариант №1. Выполните действия: 1)-12,60,6 + 4,8-(-1,3); 2) (4,3-5) (-5,16 + 5,08); №2 8)·(-1)-(-2)· 4) (5-6)-(3-0,55). Найдите значение выражения: (-):(+-)(1 2)(+):(-): 3) (-):(+): 4)-80-(-80-(-4,5): 원)·2층. №3 Решите уравнение: 1)-9x-81; 2) 0,7x--4,9; 3)-1,3x--6,5; 5)--- 4):-- 8. 6)-34-x-25. 27 7 28 No4 Выполните сложение, выбирая удобный порядок вычисле- ний: 1)-5,84 +9,77 + (-6,77) + 5,84; 2)-2,23+6,14 + 8,23 + (-10,14).

№1

1) \[-12.6 \cdot 0.6 + 4.8 - (-1.3) = -7.56 + 4.8 + 1.3 = -2.76 + 1.3 = -1.46\]

2) \[(4.3 - 5) \cdot (-5.16 + 5.08) = -0.7 \cdot (-0.08) = 0.056\]

№2

1) \[\left(-\frac{5}{18} + \frac{11}{12}\right) : \left(-\frac{69}{72}\right) = \left(-\frac{10}{36} + \frac{33}{36}\right) : \left(-\frac{23}{24}\right) = \frac{23}{36} : \left(-\frac{23}{24}\right) = \frac{23}{36} \cdot \left(-\frac{24}{23}\right) = -\frac{2}{3}\]

2) \[\left(-\frac{11}{18} + \frac{29}{45}\right) : \left(\frac{35}{54} - \frac{19}{27}\right) = \left(-\frac{55}{90} + \frac{58}{90}\right) : \left(\frac{35}{54} - \frac{38}{54}\right) = \frac{3}{90} : \left(-\frac{3}{54}\right) = \frac{1}{30} \cdot \left(-\frac{54}{3}\right) = -\frac{18}{30} = -\frac{3}{5}\]

3) \[\left(\frac{5}{12} - \frac{13}{15}\right) : \left(\frac{9}{14} + \frac{24}{35}\right) = \left(\frac{25}{60} - \frac{52}{60}\right) : \left(\frac{45}{70} + \frac{48}{70}\right) = -\frac{27}{60} : \frac{93}{70} = -\frac{9}{20} \cdot \frac{70}{93} = -\frac{3}{2} \cdot \frac{7}{31} = -\frac{21}{62}\]

4) \[-3\frac{3}{4} - \left(-8\frac{2}{9} - (-4.5) : \frac{9}{14}\right) \cdot 2\frac{1}{4} = -\frac{15}{4} - \left(-\frac{74}{9} + \frac{9}{2} \cdot \frac{14}{9}\right) \cdot \frac{9}{4} = -\frac{15}{4} - \left(-\frac{74}{9} + 7\right) \cdot \frac{9}{4} = -\frac{15}{4} - \left(-\frac{74}{9} + \frac{63}{9}\right) \cdot \frac{9}{4} = -\frac{15}{4} - \left(-\frac{11}{9}\right) \cdot \frac{9}{4} = -\frac{15}{4} + \frac{11}{4} = -\frac{4}{4} = -1\]

№3

1) \[-9x = -81\]

\[x = -81 : (-9)\]

\[x = 9\]

2) \(0.7x = -4.9\)

\[x = -4.9 : 0.7\]

\[x = -7\]

3) \[-1.3x = -6.5\]

\[x = -6.5 : (-1.3)\]

\[x = 5\]

4) \[\frac{1}{7}x = -\frac{8}{27}\]

\[x = -\frac{8}{27} : \frac{1}{7}\]

\[x = -\frac{8}{27} \cdot 7\]

\[x = -\frac{56}{27}\]

\[x = -2\frac{2}{27}\]

5) \[-\frac{2}{7}x = -\frac{1}{6}\]

\[x = -\frac{1}{6} : \left(-\frac{2}{7}\right)\]

\[x = \frac{1}{6} \cdot \frac{7}{2}\]

\[x = \frac{7}{12}\]

6) \[-3\frac{4}{7}x = -25\]

\[-\frac{25}{7}x = -25\]

\[x = -25 : \left(-\frac{25}{7}\right)\]

\[x = -25 \cdot \left(-\frac{7}{25}\right)\]

\[x = 7\]

№4

1) \[-5.84 + 9.77 + (-6.77) + 5.84 = -5.84 + 5.84 + 9.77 - 6.77 = 0 + 3 = 3\]

2) \[-2.23 + 6.14 + 8.23 + (-10.14) = -2.23 + 8.23 + 6.14 - 10.14 = 6 - 4 = 2\]